Jackson underwent an MRI on Monday that returned inconclusive results, which has left doctors to recommend the 31-year-old running back rest for 7-10 days. Following that period of inactivity, they hope to reexamine the injury and establish a timetable. However, that means playing Sunday is unlikely.
The injury was initially sustained during Sunday's loss to the New York Jets on a second quarter rushing attempt up the right side. Able to walk off the field under his own power, Jackson was seen testing the injured leg on the sidelines.
He ended the day with six carries for 15 yards.